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<br />[3 Executive Summary <br />S-20 <br />DEIS - Navajo Reservoir Operations <br /> <br />Some flexibility in reservoir releases already exists because water committed for present or <br />future development is not currently used. This may be a significant amount of water in any <br />given year and would be released downstream until used for development. The release of <br />this water could be incorporated into operations to augment a 250 cfs minimum release <br />while maintaining a target flow of at least 500 cfs downstream of FarmingtonH it also could <br />be released to extend the duration of the spring peak release. The regulation of this water <br />would be determined through the Navajo Unit operation meetings and discussions with the <br />Service. One likely scenario is to regulate this water to maintain higher late spring and <br />summer releases to the river to provide recreation, hydropower, water quality, fish and <br />wildlife, and other benefits. Unusually high inflows (other than those associated with <br />spring runoff) resulting in very high reservoir elevations would be released as a spike flow <br />if necessary to avoid an uncontrolled spill under this alternative. <br /> <br />500/5000 Alternative <br /> <br />During the public scoping process, many people and interests requested that minimum <br />releases not be reduced below 500 cfs. This alternative was included to reduce potential <br />impacts to downstream water users' ability to take water at their diversion structures and to <br />downstream recreation users (trout fishery and rafting) by maintaining higher minimum <br />releases than those under the 250/5000 Alternative. <br /> <br />Because Flow Recommendations are not fully met by this alternative, reconsultation under <br />ESA on the ALP Project, NITP completion, Florida and Mancos water contracts, and <br />3,000 acre-feet of minor unspecified depletions would be required. In addition, Navajo <br />Reservoir would infrequently (less than 1 percent of the time) be drawn down below the <br />NIlP inlet works, thus interfering with irrigation deliveries to the NIIP. Further, main- <br />taining the minimum release at 500 cfs limits the ability to develop water and results in <br />spring peak releases of lesser duration and frequency. A minimum release of 500 cfs also <br />limits the ability to meet Flow Recommendations below Farmington. <br /> <br />Even though this alternative would not fully meet the Flow Recommendations, the <br />purpose and need outlined in this DElS, or diversion demands from the Navajo Reservoir <br />water supply, it was retained for analysis because of substantial public interest and <br />concern. <br /> <br />" The 5JRBRIP Biology Committee acknowledged that some flexibility exists in meeting the upper limit of <br />1,000 cfs during the irrigation season. The Biology Committee indicated that during the irrigation season (March <br />through October) "it may not be effective or necessary to lower releases below 500 cfs until water use in the basin <br />increases to the point that the water is needed to meet runoff period recommendations. This flexibility is <br />extended only to tne irrigation season as defined. . .and only until water development reaches the level that <br />additional water is ne~ded for Spring r~l~ases." (February 21,1002, memorandum from Biology Committee to <br />Reclamation). <br />